Electroplating apparatus



March 31, 1925- 1,532,112 i C. E. JONES ELECTROPLATI NG APPARATUS Filed Sept. 22, 1923 All? PRESSURE Inverfl'. 11": Charla s ELJones,

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Patented Mar. 31, 1925.

UNITED STATES CHARLES E. JONES, OF SCHENEGTADY; NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTROPLATING APPARATUS.

' I Application filed September 22, 1923. Serial No. 664,328.

To all whom it may concern:

Be it known that I, CHARLES E. Jones, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Electroplating Apparatus, of which the following is a specification.

The present invention comprises a new electroplating apparatus which is particularly adapted for the rapid handling of large quantities o material to be plated, particularly when thg material consists of relatively small objects, It is the object of my invention to increase the capacity and efficiency of the plating apparatus and to provide convenient facilities for handling the work and the electrolyte.

In plating apparatus heretofore in use, the work, constituting the cathode, has been placed in a removable wooden barrel which was submerged during operation in an electrolyte contained in a stationary tank. The anode was constituted of metal plates .immersed in the electrolyte and supported from a rail or barabove the electrolyte. The wooden barrel was rotated during the plating operation by a rotating shaft projecting through a stufiing box in the wall of the tank.

Trouble was experienced in this apparatus by the leaking of thestufling box, the dripping of electrolyte from the wooden barrel when removed from the work, the .corrosion of the anode contacts and other parts, and the accumulation of sediment in the tank.

In accordance with my presentinvention all these difficulties are avoidedby making the container for the work, whether consisting of wood, or other insulating material, a fixed part of the electrolyte tank and constituting the tank itself the anode. Conduits are provided for charging and discharging the electrolyte, and providing water for washing the work before remov-' ing it from the plating apparatus. The platingtank is rotatable and can be tilted for reasons to be later explained. The accompanying drawings show a specific embodiment of my invention, Fig. 1 being a vertical section of the entire apparatus, and Fig. 2 an exterior perspective view of the plating tank. 7

As shown in Fig.1, the plating operation is carried out ina metal tank 1, which is rotatably mounted upon a longitudinal shaft 3 and supported upon a framework 4 by trunnions 5 and 6 (shown in dotted lines). The apparatus may be tilted in a vertical plane by a hand wheel 7, fixed upon a shaft 8 which in turn is attached by the chains 9 and 10 to a hanger 11, for the shaft 3. shaft 8 by means of the hand wheel 7, the chains are either lengthened or shortened so as to permit tank 1 to be tilted. The tilting of the tank may be arrested by a pawl and ratchet 12.

A rotative movement may be imparted to the tank through a gear and pinion 13 by a hollow shaft and pulley wheel 14, or any other suitable driving mechanism.

The tank 1, which in the drawing is shown as having a double wall, may consist of iron or any other suitable material, de-- pending on the character of the plating solution. In the case of some electrolytes, the exterior wall of the barrel preferably consists of wood. Within this tank 1 isa fixed container 16 for the work consisting of wood, celluloid, bakelite, or other suitable insulating, material, and provided with perforations through which the electrolyte may circulate. A current conveying conductor 17 projects into the space within the container 16 and passes through the shaft 3 toan external electric conductor 18, suitable electrical insulation, as indicated, being provided to insulate the conductor 17 from the shaft 3. By means of this conductor 17 current is fed to the work, which may consist of small metal parts, which during the plating operation, constitute the cathode. The tank 1 itself constitutes the anode, an electrical connection 19 being provided conveniently through the external metallic parts of the frame upon which the tank rests, as shown in Fig. 2.

Beneath the tank, and preferably below the floor level, is provided a storage tank 21 for holding, the electrolyte. A conduit 22 conveys the electrolyte from the tank 21- to the plating apparatus, this pipe conveniently being carried from a point near the bottom of the storage tank 21, to. a point above the plating apparatus so as to discharge the electrolyte directly into the plating tank. Any convenient ump arrangement may be used, the drawingshow- Upon the revolution of the i ing an,arrangement whereby the electrolyte is propelled by air under pressure introduced through a pipe 23.

When the work to be platedhas been in troduced into the tank 1 and the?" latter has been brought to' upright position, the valve '24 in the discharge conduit is; closed and the valve 26 in the air pressure pipe 23 is opened, therebyzdischarging theelectrolyte from the storage tank 21 into the plating tank 1. After a desired amount 0f"- electrolyte has been introd'uced and the valve 26 has been closed, a plating current of suitable characteristics is conveyed to the apparatus through the conductors '18, 19, the tank 1 meanwhile being placed in slow rotation. The rotation of the'tank causes an even distribution of the plating coat u on." the work and insures a circula tion 0 the. electrolyte so as to bring'fresh portions of the electrolyte in contact with the workand prevents the deposition'upon' the anode .of sediment .or chemical compounds formed in the tank, thus insuring at all times favorable electrical conditions within the plating tanku v When the plating process has been'completed, the cock 27 and the valve 24 are 1 opened to return the electrolyte to thestorage tank through a funnel 29 mm cond'uit25, A screen'or filter. is rovided as shown by dotted lines. The ve 30 in thetank is opened to allow the escape of air from the tank when the electrolyte is returned to thetank 21. Water or a suitable wash solution then is introduced by opening the valve 31 in the supply conduit 32. The wash water may easily, be removed by tilting the container sufiiciently to discharge the wash water into a screened receiver 33, which may be drained by a conduit 34. The lated' work may be discharged from t a container 16 by gravity with the wash; water. The above described operation may be repeated with another quantity. of work, 'frsh amounts of electrolyte being added from time totime to maintain a desired concentration. I,

What I claim as new and desire to, se-

cure by Letters Patent of the United States, 1s: 1. An electroplating apparatus compris ing a tank consisting in part at least of metal, a cathode projecting through the bottom of said tank and being electrically insulated therefrom, and a non-conductive container for work to be plated surround ing said cathode.

2. An electroplating apparatus comprising a--metal tank, a lon 'tudinal shaft forming a unitary part: 0 said tank, a cathode projecting through the bottom of said tank, a cathode conductor extending through said shaft, an insulating sleeve located between said conductor and said shaft,- a perforated container consisting of insulatin material surrounding said cathode and eld in fixed'relation to said tank, and a support permitting rotation of said tank and shaft. Y

- In witness whereof, I' have hereunto set my hand this 21st day of September, 1923.

CHARLES E. JONES. 

